EFFECT OF DENERVATION ON THE FUNCTION OF THE AIRWAYS

这项建议将研究肺去神经对结构的影响。 通过检验两个普遍的假设：a.增加 呼吸过程中的呼吸道劳损引发大鼠的纤维增殖反应 失神经呼吸道和B.失神经细胞产生的神经营养因子 靶基因修饰呼吸道副交感神经肽基因表达 神经节。实验方法将追求两个具体目标。这个 第一个目标将是确定去神经对 大鼠I型前胶原的转录调节。因此， 前胶原蛋白的表达将通过I原位杂交进行评估 单侧肺迷走神经切断术或同基因肺移植。差异 在去神经肺和对照肺之间的前胶原mRNA水平将是： 1.对呼吸道劳损进行实验操作后进行检查； 与含有菌株的两种生长因子的表达有关- 其基因启动子中的反应元件并可能上调胶原 转录：血小板衍生生长因子(PDGF)与转化 生长因子β(TGFβ)。第二个目标将是澄清 决定失神经人类多肽能表型的机制和 大鼠呼吸道副交感神经节。原速激肽基因的表达 产物及其受体将通过原位杂交进行研究， 溶液杂交-核酸酶保护试验和免疫组织化学 在失神经大鼠肺和通过植入大鼠呼吸道制备的异种移植物中 和人支气管移植到免疫缺陷小鼠的皮下组织中。这个 前速激肽原和神经激肽受体的合成时间分布 表现为：1.与神经激动素相关的药理作用 对支气管运动张力的贡献，2在延长神经激肽后进行评估 受体抑制；3.与神经营养因子的表达相比 通过失神经的呼吸道组织和神经节的神经营养因子受体 神经元。从这项研究中获得的信息不仅将使 目前对呼吸道神经生物学功能的了解，但 也将对肺的发病机制提供有价值的见解。 移植致闭塞性毛细支气管炎和其他潜在的呼吸道 因药物或机械破坏呼吸道通畅而造成的损伤 肌肉紧张度。

This proposal will study the effects of lung denervation on the structure and function of the airways by testing two general hypotheses: a.increased airway strain during breathing initiates a fibroproliferative response in denervated airways and b. neurotrophins produced by denervated neuronal targets modify neuropeptide gene expression in airway parasympathetic ganglia. The experimental approach will pursue two specific aim. The first aim will be to define the effects of denervation on the transciptional regulation of type I procollagen in rats. Accordingly, procollagen expression will be assessed by i situ hybridization after unilateral lung vagotomy or syngeneic lung transplantation. Differences in procollagen mRNA levels between denervated and control lungs will be: 1. examined after experimental manipulations of airway strain and 2. related to the expression of two growth factors which contain strain- responsive elements in their gene promoter and may up-regulate collagen transcription: platelet-derived growth factor (PDGF) and transforming growth factor beta (TGF beta). The second aim will be to elucidate the mechanisms that determine the peptidergic phenotype of denervated human and rat airway parasympathetic ganglia. The expressions of protachykinin gene products and their receptors will be studied by in situ hybridization, solution hybridization-nuclease protection assays, and immunohistochemistry in denervated rat lungs and xenografts prepared by implanting rat airways and human bronchi into subcutaneous tissue of immonodeficient mice. The resultant temporal profile of pre-protachykinin and neurokinin receptor expressions will be: 1. related pharmacologically to neurokinin contribution to bronchomotor tone, 2 evaluated after extended neurokinin receptor inhibition, and 3. contrasted to the expression of neurotrophins by denervated airway tissues and neurotrophin receptors by ganglion neurons. The information gained from this research will not only advance the current understanding of the biological function of airway nerves, but will also provide valuable insight into the pathogenesis of lung transplantation-induced bronchiolitis obliterans and other potential airway injuries cause by pharmacological or mechanical disruption of airway smooth muscle tone.